This invention relates to connectors and, more particularly, to flexible jumper strips.
In the construction of electrical assemblies, subsystems made on hard or flexible printed circuits are often used. These subsystems then have to be connected together with jumper cables or strips. Typically, the jumper strips are made in the form of a plurality of parallel conductors encased in an insulating layer. Such a jumper strip is shown in U.S. Pat. No. 3,221,286 issued to G. A. Fedde.
Most of the prior art jumper strips made by printed circuit techniques are relatively expensive and are also deficient in several other respects. In particular, they are either not flexible or they tend to flex or bend in the wrong areas. The weakest point is often where the pins enter the insulation. This results in a sharp crease or bend which can eventually lead to the breaking of the pin. Also, the flexing of such jumpers leads to a separation of the insulating layer from the conductor. To overcome these problems a flexible jumper made by flattening the middle portions of round wires and encasing them in insulation is disclosed in U.S. Pat. No. 3,601,755 issued to J. F. Shiells, Jr. The insulation of this jumper extends far enough up the flattened wire section to prevent the relatively stiff round wire portion from sharply bending the flattened section at the edge of the insulation. However, with such a jumper arrangement, there is little of the freedom of design that is possible with a jumper formed by printed circuit techniques. Also, the flattening of the wire may produce mechanical stresses that could eventually cause the wire to fail.